Starting switch



S- 7, 1948. F. c. DAZ'LEY ETAL 2,447,318

s'mmne sincn Filed larch 18, 1946 g Fig.2.

' i i] u .9 4

7 Fig. 5. i 9 .H 39 r- Inventors: Frederick C.Daz|e JohnM. Pistey,

Their Afitom e54 Patented Aug. 17, 1948 2,441,318 s'raa'rmc swrrcnFrederick c. Dasley, Strattord, and John M. Plstey, Fair-field, Conn,assignors to General Electric Company,

a corporation of New York Application March 18, 1946, Serial No. 655,073

' 8 Claims. (01. zoo-1c) Our invention relates to operating mechanismsfor discharge lamps and more particularly to starting switches forfluorescent lamps of the type now in commercial use. a

It is an object of our invention to provide a new and improved operatingmechanism for fluorescent lamps in which manually operable switch meansis employed to start the lamp.

It is another object of our invention to provide an improved switchmechanism for starting fluorescent lamps in which the switch is manuallyoperated by means of push buttons.

A further object of our invention is the provision of a switch mechanismwhich is small in size making it especially suitable for use in tablelamps, or the like, and in which the mechanism comprises relatively fewparts thereby providing a construction which may be manufactured at lowcost.

In the accompanying drawing, Fig. 1 illustrates a table lamp providedwith a switch constructed in accordance with our invention; Figs. 2 and3 show the switch mounted in position on the lamp holder; Fig. 4 is aview of the interior of the switch showing the parts in "011 position;Fig. 5 shows the switch parts in starting position during preheat of thelamp filaments; Fig. 6 shows the switch in "on position; Fig. 7 is acircuit diagram showing how the switch is connected between the lamp andthe current supply, and Fig. 8 is a view of a modification oi the switchstructure.

Referring to Fig. 1 of the drawing, we have illustrated a table lamp Iprovided with a lamp holder 2 on which is mounted a fluorescent lamp 3.The lamp is controlled by means of a manually operated switch 4constructed in accordance with our invention. Lamp 3 is illustrated asbeing one of the new circular fluorescent lamps now on the market. Lampholder 2 is provided with spaced arms 5 and 6, one of which is movable,so that the arms may be positioned in the loop of the lamp to supportthe lamp on the holder. As shown in Figs. 2 and 3, the arm 5 is providedwith a contact receptacle 1 for making an electrical connection with thelamp contact pins. The lamp holder itself forms no part of the presentinvention. It may be of the type disclosed in the copending applicationof Frederick C. Dazley, Serial No. 624,036, filed October 23, 1945, andassigned to the same assignee as the instant application. In such Eampholder, the body portion is constructed of two telescoping channelmembers which we have identified as l and 9 in Fig. 2. We construct ourswitch of the present invention of a size to seat within the telescopingmembers so that the switch is supported directly in the lamp holder. Inthis way, the switch is made easily accessible and is furnished with thelamp holder. It may be wired to the holder at the factory, although forthe sake of clarity, the wires have been omitted in the showing of Figs.2 and 3.

Circular fluorescent lamps of the type described are provided withfilaments at each end of the discharge tube, the latter being bent inthe form of a circle. Such a lamp is shown schematically in Fig. 7. Asis well understood in the art, the lamp is started by first passing aheating current through the filaments until they reach an electronemitting temperature. At that time, a high voltage is applied from theassociated ballast in the system so that a glow discharge-takes placebetween the filaments lighting the lamp. Our switch is designed foroperation in such a system and is manually operated to preheat the lampfilaments and apply the high voltage kick from the ballast.

Turning now to the construction of the switch and referring to Figs. 4,5 and 6, the switch 4 is provided with a housing in formed of suitableinsulating material, such as a molded plastic. The housing is formedwith a recess II which is separated into two chambers l2 and H by astrip of insulating material H, such as sheet fiber. The strip rests inrecesses l5 formed in opposite walls of the recess. A pair of linecontacts i6 and H are mounted in recesses ill in opposite walls of thehousing. One end of each contact extends into chamber l2 in position tobe engaged by the movable contact balls l9. The outer ends of thecontacts l6 and I! are connected to the lamp ballast 2i and one of thelamp filaments 22, respectively, as shown in Fig. '7. Each contactcomprises a blade punched from sheet bronze, or the like; each one isformed with a projecting tang (not shown) which, engages the bottom wallof the chamber l2 and prevents the contact blades from slidinglongitudinally out of the housing. A pair of starting contacts 23 and 24are likewise carried by the housing and extend into the chamber l3. Theyare similar to contacts is and I1 and are held in the housing in likemanner. As shown in Fig. '1, contacts 23 and 24 are connected to lampfilaments 25 and 22, respectively.

The switch is provided with an operating push button 26 having a plunger21 resting in chamber i3 and extending into an opening 28 in the fiberplate l5. The button extends throughan opening 29 in the wall of therecess so that it is accessible for operation of the switch. A coilspring 33 is mounted on the plunger 27 and biases the button 23outwardly, outward movement being limited by a. flange 3i which engagesthe inner wall of the recess. In order to make an electrical connectionacross the contacts 23 and. 24, the plunger carries a contact blade orplate 32 which may be moved into engagement with the fixed contacts.Spring 33 holds the blade 32 in position on the plunger.

A second operating button 33 is mounted on the opposite side of thehousing in opposed relation to the button 23. It likewise extendsthrough an opening 34 in the wall of the housing and its outwardmovement is limited by a flange 35. The aforementioned contact balls l9are mounted in a cylindrical tube 33 which, in

turn, is fastened to the fiange of button 33 in any suitable manner asby a pin (not shown). The tube 36 may be formed of insulating material,such as a molded plastic, or it may be made of metal since it is carriedby the insulating button 33. In any event, the contact members I9 arefree to slide or rotate toward and away from each other within the guidetube 33 and they are biased outwardly by means of a coiled compressionspring 37. Spring 33 is made of good conducting material such asphosphor bronze wire and the contact balls i9 are preferably made ofbrass so that they will make a good electrical connection with the fixedcontact blades l6 and I1. It will be manifest that tube 36 carrying thecontact balls i3 will be moved back and forth with movement oi operatingbutton 33. In one position, the contact balls will be biased outwardlyinto engagement with the side walls of recess II on one side ofprojections 38, as shown by Fig. 4. In the other position, the contactballs will be spring biased into engagement with the contact blades l6and i! on the other side of projections 33, as shown in Fig. 5.

The switch mechanism thus far described is easily assembled on thehousing simply by placing the parts in the recess and slots in thehousing. The parts are then held in assembled relationship by means ofa. cover plate 39, as shown by Figs. 2 and 3. The cover plate is punchedfrom insulating material, such as sheet fiber, and is fastened to thehousing by means of selftapping screws 40 extending into openings M inopposite walls thereof.

The operation of the switch is illustrated in Figs. 4 to 7, inclusive.Fig. 4 shows the switch in oif" position; Fig. 7 includes a diagrammaticshowing of the switch, likewise in off position,

with the switch connected into a lamp operating circuit which includes aballast 2i and current supply leads 4243 which may be a standard 110volt A.-C. current source. Ballast 2i may consist of a choke coil or anauto transformer, such devices now being commercially available.

To start the lamp, operating button 26 is depressed. Plunger 27 engagesthe tube 36 and forces the tube 36 and contact balls l9 to snap past theprojections 33 to a position such that the contact balls engage thelinecon'tacts l6 and I1, as shown by Fig. 5. At the same time, contactplate 32 is moved into engagement with starting contacts 23 and 24.Current now flows from line 42 through ballast 28, contact l6, contactballs I9 and spring 31, contact ll, lamp filament 22, contact 24, plate32, contact 23, lamp filament 25 to the other supply line 43. In thisway, current flows through the lamp filaments to heat them to anelectron emitting temperature. Accordingly, this position of the switchis known as the preheat" position. Button .28 is held manuallydepressed, with the contact plate 32 electrically connecting contacts 23and 24 for a period of time sufilcient for the lamp filaments to heatup. Usually, this time is on the order of one second. Button 26 is thenreleased so that spring 30 moves plate 32 away from the startingcontacts23 and 24. This opens the circuit across the lamp filaments. Dueto the magnetic decay in the ballast occasioned by the suddeninterruption of current, a high voltage kick is applied to the ballastacross the filaments causing the lamp to light. The switch is now in the"on position, shown by Fig. 6. The spring 31 holds the contact balls l3firmly in engagement with the contacts l6 and i1, thereby maintainingthe circuit to the line supply closed.

Button 33 is depressed to turn the lamp off. This moves the contactballs 59 out of engagement with contacts i6 and H to a position on theother side of the projections 38, so that the line supply of current isinterrupted. The switch hasnow been returned to off position shown byFig. 4. Due to the biasing action of spring 31, the contact balls moveto one side or the other of projections 38 with considerable snapaction. This means that the switch mechanism is held securely in "on orofi position. When the switch is in 01? position, the power supply tothe lamp filaments is maintained open. In this way, no power loss canoccur in the ballast when the lamp is not lighted.

A modification of the switch construction is shown in Fig. 8. Operatingbutton 26 is provided with a shoulder 44 which engages a, flexiblespring contact arm 45 fastened to contact blade 23. The spring armcarries a contact point 46 which mates with a similar point 47 oncontact blade 24. It will be apparent that when button 26 is pushedinwardly, blade 45 will flex permitting contact points 46 and 4'? toclose. This will close the starting contacts in the manner alreadydescribed. Button 26 is provided with an extension 48 which is adaptedto engage a conducting disk 49 screw threaded into the end of button 33.Since button 33 is constructed of insulating material, the circuitthrough contacts l6 and I! will be closed only when they engage disk 49.The contact blades [6 and l! extend intothe recess H and frictionallyengage the side walls of the button 33 so that the button is securelyheld in any one of its two positions.

Fig. 8 shows the switch in off position. To light the lamp, the button26 is pushed inwardly. This movement closes contacts 46 and 41 andextension 48 pushes button 33 to a position such that conducting disk 49is engaged by contact blades l6 and H. In this position of the switch,preheat current flows through the lamp filaments in the manner alreadydescribed. Button 26 is then released so that spring blade 45 returns itto its original position and at the same time opens the circuit throughthe starting contacts 23 and 24. This lights the lamp. To turn the lampoil, operating button 33 is pushed inwardly to a position such that theinsulating portion of the button is placed between contact blades I6 andI1. Outward movement. of button 33 is limited by a flange 50 whichengages the side wall of recess l i. Inward movement is limited by disk49 engaging extension 48. The modification of Fig. 8 has the advantagethat the construction has been simplified by reducing the number ofparts thereby providing a construction which may be manufactured atlower cost.

Our switch is one which comprises relatively few parts providing a lowcost item. The two push button operating members 28 and 33 provide aswitch mechanism which is easily operated particularly when the switchis mounted in the relatively narrow channel of the lamp holder 2. Ifdesired, the button 25 may be manufactured of colored plastic material,such as red compound, in order to provide identification oi the properbutton to push to turn the switch on.

What we claim as new and desire to secure by Letters Patent of theUnited States is:

1. An electric switch comprising, in combination, a housing 01'insulating material, spaced contact members carried by said housing, apush button movable relative to said contact members, conductin meanscarried by said push button including spring biased ball contactsengaging said contact members for closing a circuit therethrough and aseparate switch mechanism carried by said housing and including a pushbutton provided with operating means cooperating with thefirst-mentioned push button to move it'to circuit closing position.

2. An electric switch comprising, i combination, a housing of insulatingmaterial, spaced contact members carried by said housing, a push buttonmovable relative to said contact members, conducting means carried bysaid push'button including spring biased ball contacts engaging saidcontact members for closing a circuit therethrough, a separate switchmechanism carried by said housing, said mechanism including a plungeradapted to engage said push button to move it to closed circuitposition, and sprin means normally biasing said switch mechanism to opencircuit position.

3. In a switch mechanism, a housing of insulating material having twochambers separated by an insulating wall, spaced contact members locatedin one of said chambers, a push button provided with a contact plate forengaging said contact members to close a circuit therethrough, said pushbutton being provided with a plunger extending through said insulatingwall, spaced contact members located in the other of said chambers, anda circuit controlling mechanism in said other chamber cooperating withsaid second-mentioned contact members, said mechanism including atubular casing open at its ends and having therein a conductive springand a pair of conductive balls, one at each end opening, said ballsbeing tensioned apart by said spring and said balls and spring beingadapted to contact and to close an electrical circuit between saidsecond mentioned contact member, the said plunger cooperating with saidcircuit controlling mechanism to move it to circuit closing positionupon operation of said push button, the circuit controlling mechanismitself being provided with a push button to move it to circuit openingposition.

4. An electric switch comprising in combination, a housing of insulatingmaterial, spaced contact members carried by said housing, a push buttonmovable relative to said contact members, conducting means carried bysaid push button including a casing containing spring biased ballcooperating with said casing on said first mentioned push button to moveit into circuit closin position.

5. An electric switch comprising in combina tion, a housing ofinsulating material, spaced contact members carried by said housing, apush button movable relative to said contact members, conducting meanscarried by said push button including a casing containing spring biasedball contacts adapted to engage said contact members or closing acircuit therethrough, opposed projections on opposite walls of saidhousing positioned so as to be engaged by said balls to provide definiteopen circuit and closed circuit positions for said push button and aseparate switch mechanism carried by said housing and including a pushbutton provided with a plunger adapted to engage said casing of thefirst mentioned push button to move the latter into circuit closingposition.

6. An electric switch comprising, spaced stationary contact members, asnap action push button mechanism adapted to remain ineither opencircuit or closed circuit positions and having movable conductive meansadapted in closed circuit position to engage said contact members toclose a circuit therethrough, a separate second push button mechanismnormally biased to open circuit position and means cooperating with bothof said mechanisms to move said snap action mechanism just beyond itsdead center when the second push button mechanism is moved to closedcircuit position, whereby said first push button mechanism snaps intoclosed circuit position when the second push button is closed.

7. In a switch mechanism, a, housing of insulating material having twochambers separated by an insulating wall, spaced contact members locatedin one of said chambers, a push button provided with a contact plate forengaging said contact members to close a circuit therethrough, meansbiasing said push button to open circuit position and said push buttonbeing provided with a plunger extending through said insulating wall,spaced contact members located in the other of said chambers, a snapaction circuit controlling mechanism in said other chamber cooperatingwith said second mentioned contact members, the said plunger cooperatingwith said snap action mechanism to move it just beyond dead centerwhereby said circuit controlling mechanism snaps into closed circuitposition upon operation of said push button, the circuit controllingmechanism itself being provided with a push button to return it to opencircuit position.

8. In a switch mechanism, a housing of insulating material having twochambers separated by an insulating wall, spaced contact members locatedin one of said chambers, a push button provided with a contact plate forengaging said contact members to close a circuit therethrough, said pushbutton being provided with a plunger extending through said insulatingwall, spjaced contact members located in the other of said chambers, anda circuit controlling mechanism in said other chamber cooperating withsaid second-mentioned contact members, said mechanism including atubular casing open at its ends and having therein a conductive springand a pair of conductive balls, one at each end opening. said ballsbeing tensioned apart by said spring, said balls and spring beingadapted to contact and to close an electrical circuit between saidsecond mentioned contact member, and opposed projections on oppositewalls of said housing in said other chamber positioned to cooperate withsaid balls to provide definite open circuit and closed circuit positionsfor said mechanism, the said 8 plunger cooperating with said circuitcontrolling REFERENCES CITED mechanism to move it to circuit closingposition upon operation of said push button, the circuit g gig g i fff tare of record m the controlling mechanism itself being provided with p apush button to move it to circuit opening posi- 5 UNITED STATES PATENTStion - Number Name Date FREDERICK C. DAZLEY. JOHN M. PIS; 1,174,492Glover Mar. 7, 1916

